A) Variance = 10.24
B) Standard Deviation = 3.2
One of the measurements of dispersion is the standard deviation, which is exclusively used for quantitative data. It aids in determining if the data's mean is a suitable measurement to reflect the core value.
TIME FREQUENCY(f) MIDPOINT(x) d d² fd fd²
0 - 0.9 43 0.45 -3 9 -129 387
1.0 - 1.9 17 1.45 -2 4 -34 68
2.0 - 2.9 19 2.45 -1 1 -19 19
3.0 - 3.9 18 3.45 0 0 0 0
4.0 - 4.9 14 4.45 1 1 14 14
5.0 -5.9 16 5.45 2 4 32 64
∑f = 127
∑fd = -136
∑fd² = 552

Standard Deviation = 

√4.35 - √1.15
Standard Deviation = 3.2
(SD)² = (3.2)² = 10.24
Variance = 10.24
To know more about standard deviation, refer to this link :
brainly.com/question/12402189
#SPJ1
Answer:
An arrow diagram
Step-by-step explanation:
Helps keep track of intricate relationships between variables. Specifies the phenomena of interest: independent, alternative, antecedent and intervening.
-Time on the bottom with an arrow
-Antecedent -> Independent -> intervening-> dependent
An arrow diagram is defined as a process diagramming tool used to determine optimal sequence of events, and their inter-connectivity. It is a network diagramming technique in which activities are represented by arrow, used for scheduling and to determine the critical path through nodes. The arrow diagramming method shows the required order of tasks in a project or process, the best schedule for the entire project, and potential scheduling and resource problems and their solutions. The arrow diagram lets you calculate the "critical path" of the project the flow of critical steps where delays can affect the timing of the entire project and where addition of resources can speed up the project.
One headed arrow connecting two variables= "X directly causes Y"
Answer:
acute
Step-by-step explanation: